摘要
Sunlight-induced photocatalytic carbon dioxide(CO_(2))reduction to energy-rich chemicals by metal-free polymeric carbon nitride(CN)semiconductor is a promising tactic for sustained solar fuel production.However,the reaction efficiency of CO_(2)photoreduction is restrained seriously by the rapid recombination of photogenerated carriers on CN polymer.Herein,we incorporate 2-aminopyridine molecule with strong electron-withdrawing group into the skeleton edge of CN layers through a facile one-pot thermal polymerization strategy using urea as the precursor,which renders a modified carbon nitride(ACN)with extended optical harvesting,abundant nitrogen defects and ultrathin nanosheet structure.Consequently,the ACN photocatalyst with desirable structural features attains enhanced separation and migration of photoexcited charge carriers.Under visible light irradiation with Co(bpy)^(2+)_(3)as a cocatalyst,the optimized ACN sample manifests a high CO_(2)deoxygnative reduction activity and high sta-bility,providing a CO yielding rate of 17μmol h^(-1),which is significantly higher than that of pristine CN.The key intermediates engaged in CO_(2)photoreduction reaction are determined by the in situ diffuse reflectance infrared Fourier transform spectroscopy,which sponsors the construction of the possible photocatalytic CO_(2)reduction mechanism on ACN nanosheets.
基金
supported by the National Key R&D Program of China(2021YFA1502100 and 2022YFE0114800)
the National Natural Science Foundation of China(22372035,22302039 and 22311540011).